Modal decomposition and equivalent circuit representations of lossless coupled multiwire lines
Abstract
Equivalent circuit representations and propagation modes on lossless coupled nwire transmissionlines are assumed to satisfy Telegrapher's equations presented by the matrix partial differential equations. It is shown that the equivalent circuit for the nwire line can be represented to be a cascade connection of Ideal transformer Interconnections (ITI), a set of n transmission lines (in the mode space) and ITI. The transformation matrix for the ITI can be classified into three types: (A) an orthogonal matrix, (B) a product of diagonal and orthogonal matrices, and (C) a product of orthogonal, diagonal and orthogonal matrices. Three kinds of characteristic impedances are described: n characteristic impedances for n lines in the mode space, the characteristic impedance matrix and nxn characteristic wire impedances. It is also shown that the biorthogonality of propagation is satisfied among voltage propagation modes and current propagation modes. An even mode and an odd mode supported on a symmetrical twowire line are extended into propagation modes on nwire lines, and a voltage even mode and current odd modes are obtained.
 Publication:

In its Equivalent Circuit Representation of Coupled Multiwire Line and Its Appl. p 732 (SEE N7733403 2433
 Pub Date:
 1977
 Bibcode:
 1977ecrc.nasa....7N
 Keywords:

 Equivalent Circuits;
 Lossless Equipment;
 Propagation Modes;
 Transmission Circuits;
 Lossless Materials;
 Network Analysis;
 Transmission Lines;
 Electronics and Electrical Engineering